John Snyder

Essential tremors, a nervous system disorder that causes rhythmic shaking, while not typically considered dangerous can have a severe impact on an individual's quality of life and daily activities. In John Snyder's case, the trembling in his hands became so disruptive, he was forced to use a stamp with his signature rather than sign his own name.

"The shaking start in the mid-1980s, mostly in my left arm and hand, which caused problems since I'm left-handed," explains the 73-year-old Brick resident. "It got worse over the years but I wound up actually having to learn to eat with my right hand."

Eventually, John sought treatment for his tremors with neurosurgeon Ty J. Olson, M.D., F.A.C.S., medical co-director of The Gamma Knife Center at Monmouth Medical Center. John has been a patient of Dr. Olson's for a few years, having undergone surgery on his spine for stenosis and placement of a shunt for hydrocephalus. As John's symptoms from these other ailments began to abate, his tremor became more pronounced and debilitating. Dr. Olson and the Snyder family had several conversations regarding Gamma Knife Radiosurgery for tremor, the risks and the new clinical trial he and radiation oncologist Sang Sim, M.D., medical co-director of The Gamma Knife Center, were running. Once the trial was opened, Dr. Olson offered to enroll Mr. Snyder.

John expressed interest immediately. He said, "Gee, I'd love that because this is getting a lot worse!" "My speech wasn't affected yet but the trembling was very pronounced in both hands and arms, I was beginning to get a tremor on my right said," says John.

Within a short period of time, John visited Monmouth Medical Center for an appointment at the Neuroscience Institute, where he met with Dr. Sim, a nurse practitioner and nurse coordinator. Following a brief interview and battery of tests, they confirmed that John was indeed a good candidate for Gamma Knife treatment – a non-invasive approach to alleviate the symptoms associated with essential tremors.

Traditionally, a neurologist would treat a patient with essential tremors with any one of a number of medications. If the patient doesn't find some relief or improvement, the neurologist may move on from medication therapy to more definitive intervention. John had failed these medications long ago.

"The most common surgery for essential tremors is deep brain stimulation, in which a neurosurgeon installs a device in the brain to send electrical impulses to specific parts of the thalamus. Although there are surgical risks associated with this procedure, it can be quite effective," explains Dr. Sim. "A less common approach uses radio frequency thalamotomy which targets the thalamus. However, a patient may not be a good candidate due if they have other medical complications, if they are on blood thinners or have cardiac complications, as John does. Gamma Knife radiosurgery, however, provides a treatment option for patients who otherwise are not candidates for traditional procedures."

Gamma Knife surgery, when used for essential tremors creates a tiny lesion in the precise location of the brain where the tremors are thought to be hyperactive. Rather than inserting a device, such as in deep brain stimulation, Gamma Knife radiosurgery zaps the area with 201 pinpoint rays, allowing for patients with severely debilitating tremors to be treated.

On the morning John was schedule to undergo the procedure with Drs. Olson and Sim, he arrived at the hospital bright and early to prepare.

Before the real treatment began, the physicians needed precise measurements of John's brain, in order to correctly beam the Gamma Knife's rays. After administrating local anesthesia and anti-anxiety medications, the medical team placed a carefully measured halo on John's head, secured with four pins. The head frame, in addition to an MRI and CT scan, would guide Drs. Olson and Sim as they administered treatment.

"We treat the thalamus on the contra-lateral, or opposite, side. In John's case, the problem was on the left side so we treated on the right side of the brain," says Dr. Sim. "The patient lies on the table in the Gamma Knife unit, while the halo is secured to the table. We then have the ability to move the table as we direct beams via the Gamma Knife to the particular part of the brain we're targeting, careful to avoid normal areas. After less than two hours, the procedure was complete and all we needed to do was remove the frame and place band aids at the points where it had been secured. All the while, John was nearly pain-free."

Home within only hours after arriving at Monmouth Medical Center that very morning, John and his physicians expected results over the course of weeks. John, however, was an early responder to the treatment.

"After six weeks I returned for a check- up, and then again six weeks later to replicate the initial tests used to determine if I was a good candidate, but even prior to that I could tell I had made progress," says John. "I was able to switch back over to eating with my left hand and I didn't have to use two hands to steady a full glass of water – I could do it with one."

Today, John continues to have check-ups and CT scans every three months to monitor his progress. He couldn't be more pleased with his treatment and is hopeful that Dr. Sim and Dr. Olson will see enough progress that he will have the opportunity to have the left side of his brain treated to make his right side tremor free as well.

"In this process, you're not a rabbit – you're the turtle," he says. "My writing was hardly legible prior to the procedure. I used my stamp for many years to sign checks and complete forms. It has taken time but I can sign my name now. Many hobbies I used to have, like scuba diving and teaching flying lessons went to the wayside. While I'll never fly again, I might be able to scuba dive again sometime soon – overall, I'm a pretty happy camper."